ASoC: ak4613: convert to SPDX identifiers

/*

 * ak4613.c  --  Asahi Kasei ALSA Soc Audio driver

 *

 * Copyright (C) 2015 Renesas Electronics Corporation

 * Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>

 *

 * Based on ak4642.c by Kuninori Morimoto

 * Based on wm8731.c by Richard Purdie

 * Based on ak4535.c by Richard Purdie

 * Based on wm8753.c by Liam Girdwood

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation.

 */

// SPDX-License-Identifier: GPL-2.0

//

// ak4613.c  --  Asahi Kasei ALSA Soc Audio driver

//

// Copyright (C) 2015 Renesas Electronics Corporation

// Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>

//

// Based on ak4642.c by Kuninori Morimoto

// Based on wm8731.c by Richard Purdie

// Based on ak4535.c by Richard Purdie

// Based on wm8753.c by Liam Girdwood

#include <linux/clk.h>

#include <linux/delay.h>